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After 150 hours on my Sierra the nose wheel decided to split at the hub. Luckily the fork kept it contained and no damage. I decided to put a Matco 4 inch nose wheel on and all that was needed was a new axle as the bearings are .675 in rather than 15 mm. All went well until the test fight where nose wheel shimmy occurred. So violent it tore 2 in slots in the spat attachment holes. Took the spat off and decided to overhaul the leg. Mine has the small diameter leg where any wear will show up as sideways movement. I redrilled the attachment holes and reamed them to new bolts. No movement. Next time I will go to the bigger diameter leg. All back together. Tightened the damper so plenty of friction. All ok but still not real sure on landing. Next move was to lower the tyre pressure from 30 psi to 20 psi. This made the treads all touch where before only the centre tread touched the tarmac. It now feels great. The old tyre was flat profile where the new one is more rounded. Spat will go back on next week. Hope this helps all who need to replace their nose wheel. I will post photos next week.

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That got my attention, Graham. I guess any lightweight alloy wheel hub can fail.

Mine are very thin one-piece wheels and cop some punishment when mounting a tyre.

Much rather bolted-together halves.

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I will post pictures later but the old one was pressed steel and cracked around the weld to the hub. The new one is aluminium and in 2 halves bolted together and I’m a lot more confident with this type of wheel.

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Aircraft Spruce / Sky Shop. NW 40 B Matco. Cost a fortune ($480) with a aircraft tyre and tube but no modifications other than the axel. The exchange rate has improved since then though. Ray T says he will have them turned up at that price but you just have to get over there it.

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I got a price for the same direct from Matco $US165.00 plus freight of $US90.00. At the time everything was beginning to shut down so I left it & still have the steel wheel. I need to replace my nose leg as the one Ray supplied while a lot stronger than the original one I bent, needs 10 deg more bend. I can't put the spat on as the spat nose drags on the ground when pulling the plane into my hangar & it takes full power & brake to straighten up if I turn tightly. The reason for less bend was apparently to reduce shimmy but I never had that anyway. I am sure it would though with the round profile tyre. I've got a metre of 1 1/4" .095 normalised Chromolly so just need it bent & tempered & I'll get the new nose wheel. It still looks good after 140 hours & about 300 landings. Touch wood. I've just replaced the Airhawk mains tyres as they were completely bald.

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I think that wheel is a little different and more durable than a wheelbarrow wheel!

For a start, wheelbarrow wheels are not welded, they comprise two sections of light pressed metal bolted together over a stand-alone centre hub section.

Wheelbarrow bearings and axles are only half the diameter of the wheel that Graham has posted the photo of.

 

https://www.nomaallim.com/wheelbarrow-tire-repair.html

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The old wheel had proper bearings which you had to fit and discard the roller bearing that came with the wheel. It looked like a wheelbarrow/ trolly wheel but was better than it looked. The crack that developed was probably a flaw in the weld that propagated around. They not available anymore so the upgrade to the alloy wheel is the way to go. Ray says he can design a completely new fork and wheel which would also be a good option but it would need testing.

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That weld hasn't penetrated. Shimmy happens to a lot of nosewheels, and tailwheels too. A damper might be a good idea. Bit serious when it happens. Nev

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That weld hasn't penetrated. Shimmy happens to a lot of nosewheels, and tailwheels too. A damper might be a good idea. Bit serious when it happens. Nev

Getting the tailwheel pivot exactly vertical is important; not easy if its suspension arm flexes with the bumps.

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